OP,
Solid state drives are reasonably reliable when used constantly so if they're attached to your computer and you're using them all the time. This refreshes the memory with power. But for long-term storage, they are not. It's much better to have discs and discs are cheap. When not in use the data does not deteriorate over a few years. I always have a minimum of two.backups of everything. You can get an attachable USB drive with 8tb for $150. You can rotate the two extra ones or you can keep one attached all the time and put one in the closet. Sounds like you simply want long-term storage so just make two copies and two different discs and throw them in the closet.
You can also get raid boxes that attach to your computer or that attach to your network. I have both. I wouldn't do it. They can be useful, but they are complex. They have many different ways to configure them with different reliabilities and data requirements. For instance, you'll generally need twice as much data storage capacity than data. This just goes on and on and you can end up like me with 100 TB in your house.
Under no circumstances trust back up software that stuff is so unbelievably unreliable. It's amazing. Not only did I have trouble at home when I ended up in charge of data centers the backup software that cost hundreds of thousands of dollars didn't work until we played with it for months, so stay away from that stuff.
Absolutely keep it simple. Otherwise, you're gonna become an IT guy.
Also consider the concept of sunk cost. I understand the feeling of the value of this material so if you just make a couple copies, you'll be feel comfortable.

